1. Field of the Invention
The subject invention relates to a holding frame and a mat assembly for absorbing liquid materials, such as oil, solvents and water based solutions and emulsions.
2. Description of the Related Art
Many industrial machines and automotive vehicles are known to splatter or drip fluids, such as oil solvents, water and the like. For example, many industrial machines employ oil to lubricate moving parts. Gaskets and seals between moving and stationary parts invariably wear and create the potential for leakage of the lubricant. Other industrial machines employ a lubricant at the interface of a tool and work piece. The lubricant can splatter while the work is being performed, and some of the splattered lubricant is likely to be deposited on the floor near the machine. Automotive vehicles also are likely to drip oil while the vehicle is idling and/or while lubricant is being added or changed. Thus, areas where a vehicle will park or idle and areas where a vehicle will be worked on often will have oil deposits on the floor. An accumulation of lubricant on a floor can be hazardous to workers or pedestrians. Additionally, the accumulated lubricant conceivably could be a fire hazard.
Sorbents commonly are used on an area of a floor near an industrial machine that is apt to drip or spray a lubricant. Sorbents come in many different forms, including elongate tubes filled with particulates of sorbent material and mats of non-woven sorbent fiber. Mats are particularly desirable for many applications in that the mat can be walked upon by workers and/or other people who must traverse the oil-splattered floor. The prior art sorbent mats may be formed from non-woven fibers of polypropylene or polyester or blends of such synthetic fibers and recycled cotton fibers. The fibers may be placed in a mat configuration by any of several well known techniques, including needle punch, melt blown, air laid, carded and spun bond techniques. The mats of sorbent fibers also may be laminated with films and composites. Non-woven mats of sorbent material with a thickness of about xe2x85x9xe2x80x3-xe2x85x9cxe2x80x3 can provide an acceptably high degree of absorbency at a reasonable price. Furthermore, these thin non-woven fiber mats are easy to transport and store prior to use and are packaged easily for recycle after saturation. However, thin non-woven fiber mats can be moved in advertently with relative ease. Thus, forces generated by a person walking on a thin non-woven fiber mat, forces generated by a vehicle moving over the non-woven fiber mat or forces generated by air currents can cause the thin non-woven fiber mat to shift from its desired location. Similarly, these same forces can cause the prior art non-woven fiber mat to fold or crease, thereby creating a raised surface on which a worker may trip. Thus, the mat that is intended to avoid a slippery dangerous surface actually can contribute to its own hazardous condition.
The prior art includes several thick, heavy, resilient fatigue mats that are used near work benches, retail counters and the like where workers are likely to stand for long periods of time. Fatigue mats are intended to improve foot and leg comfort, but typically do not absorb liquids. Fatigue mats typically are not very flexible, and hence are not likely to shift, fold or crease. However, the bulk of these prior art mats also make them more costly, and more difficult to ship, store and install. Attempts have been made to utilize the heavy thick characteristics of the fatigue mat to an advantage. For example, the prior art includes fatigue mats formed from several interengageable pieces, that are locked to one another in the manner of a jigsaw puzzle. The assembled pieces can be disassembled for discard or repositioning. The above-described cost and weight characteristics would make these types of prior art mats unacceptable for environments where frequent replacement is necessary, as is the case with sorbent mats that are intended to absorb liquid materials. Furthermore, the jigsaw puzzle type of mats are limited to certain sizes and shapes that are dictated by the sizes and shapes of the various components. Conceivably these prior art mats could be cut to match the specific sizes and shapes of an area. However, the thickness and rigidity that enable the respective jigsaw parts to be assembled also complicates cutting the parts. Furthermore, a cut edge of a thick mat can define a surface discontinuity over which a worker may trip.
In view of the above, an object of the invention is to provide an inexpensive lightweight sorbent mat that can be installed securely and removed easily and quickly.
It is another object of the subject invention to provide a lightweight inexpensive absorbent mat that can be adapted to any convenient size and shape.
The subject invention is directed to a mat assembly that comprises a sorbent mat and a frame for overlying at least certain peripheral regions of the mat. The frame is sufficiently heavy to securely hold the sorbent mat in place. However, the frame can be separated from a spent sorbet mat and reapplied to a new sorbent mat. Thus, the sorbent mat is disposable and/or recyclable, while the frame is reusable.
The mat may comprise a non-woven array of fibers and may have a backing layer on one side of the array of fibers. More particularly, the mat may comprise a nonwoven array of randomly oriented polypropylene fibers, an array of polyester fibers, or a blend of either of these synthetic fibers with other fibers. For example, the mat may comprise a non-woven array of polyester and cotton fibers with a latex binder on one side. The non-woven array may be achieved by any of several known technologies, such as melt blown, spun bond, ultrasonic, airlaid or needle punch or a combination of these.
The frame of the mat assembly preferably is formed from an elongate retention strip that is extruded or molded from a flexible synthetic material, such as an elastomer or rubber. The elongate retention strip has a bottom surface, a top surface and opposed longitudinal side edges. The bottom surface of the retention strip may be substantially planar, whereas the top surface of the retention strip may be tapered to narrower thicknesses at each of the opposed longitudinal side edges. Thus, the elongate retention strip of the frame may define a maximum thickness centrally between the side edges and may define reduced thicknesses in proximity to the side edges.
The bottom surface of the retention strip from which the frame is formed has attachment means disposed at least at certain locations thereon. The attachment means may be attached during or after the extrusion or molding of the retention strip. The attachment means may comprise an array of hooked filaments that are releasably engageable with the fibers of the mat. For example, the attachment means may comprise one half of a Velcro assembly. The attachment means preferably comprises an elongate continuous ribbon or tape disposed along substantially the entire length of the bottom surface of the retention strip. However, a plurality of spaced apart attachment segments may be disposed at selected locations along the bottom surface of the retention strip. The attachment means may cover the entire bottom surface of the retention strip. However, it is sufficient and preferable to have the attachment means disposed centrally between the side edges of the retention strip. The attachment tape or attachment segments may be affixed to the bottom surface of the retention strip by adhesive. Alternatively, a non-adhesive affixation of the attachment means to the retention strip may be employed.
The retention strip may be a coextruded structure with at least one section having a visual contrast. The contrasting section preferably is disposed at least on the upper surface of the retention strip and may be disposed centrally between the side edges of the retention strip. For example, a major portion of the retention strip may be extruded from a black elastomeric material, while a central portion of the retention strip may define longitudinally extending design, logos or printing. For example, a different color (e.g., yellow) may be provided as a warning signal.
The mat assembly is employed by cutting the non-woven mat to a desired size and shape for the intended application. Mats of this type typically can be cut with a conventional scissor. The frame assembly has a size and shape corresponding to the size and shape of the periphery of the mat. More particularly, the frame assembly is formed from a plurality of retention strips. The retention strips may be pre-molded to specified dimensions. Alternatively, the retention strips can be cut with a utility knife, utility shears or heavy duty scissors for form the frame assembly. The bottom surfaces of the cut retention strips then merely are laid on the top surface of the mat. The Velcro or other attachment means on the bottom surface of the retention strips will releasably engage the non-woven fibers on upper peripheral regions of the mat. Thus, peripheral regions of the mat will be held in a substantially planar orientation on the substrate by the weight of the frame. Furthermore, the engagement between the bottom surface of the retention strip and the non-woven fiber array of the mat will prevent the frame from moving relative to the mat.
The frame assembly can be formed by cutting the retention strip at an acute angle (e.g., 45xc2x0) at locations corresponding to the corners of the mat. Alternatively, the retention strip can be formed from a plurality of segments of specified length. The segments may be pre-molded or otherwise formed to have 45xc2x0 corners. The retention strips preferably are symmetrical in cross-section, and hence a plurality of pre-formed retention strips with 45xc2x0 ends can be butted to one another merely by reversing alternate strips to define a retention strip of any desired length. Thus, the frame effectively is mitered to overlie the corners of the mat. Alternatively, the frame assembly may comprise corner sections that extend through 90xc2x0 at either an internal or an external corner. The remaining portions of the retention strips then can be cut at right angles to the longitudinal direction of the retention strip, and the strip may merely be butted against the corner pieces.
The mat will remain planar and stationary due to the cooperation with the retention strips, and particularly the attachment portions on the bottom surface of the strip. The tapered configuration of the strips will substantially prevent accidental tripping by workers or other pedestrians near the mat assembly. Additionally, the preferred coextruded multi-color strips enhance visible detection of the mat assembly, and further reduce the likelihood of accidentally tripping over edge portions of the mat assembly. Oil or other liquids that may be deposited on the mat assembly will be absorbed by the nonwoven fiber array of the mat. The bottom layer or backing sheet of the mat will prevent any such oil or liquids from permeating through the mat and onto the substrate. When the mat approaches saturation, the strips need merely be peeled away from peripheral regions of the mat. The mat then may be discarded or recycled in the conventional manner for such sorbent mats. A new section of mat then can be cut from a roll and placed on the section of the substrate that had previously been protected by the removed saturated mat. The previously employed retention strips of the frame assembly then can be repositioned around the periphery of the new mat.